Cooled electrical apparatus



1949 R. E. HERR ETAL COOLED ELECTRICAL APPARATUS Filed June 22, 1945 ATTORNEY Patented Dec. 27, 1949 PATENT omc'e 2,492,747 cooLfEnELsc'rRIcA APPAR TUS Russell' E. fieir',;Mi int E hniim; and La es 1:. Anderson, Collingswood, N, J., assi'gnors to Radio Corporation of America; a; corporation of Delaware.

iiiip icaiiiiii 1611822, 194iseria'1 no. 600,800-

2' claims;

.frhi finv llib mate to e eiule e -f ficq d n e wh ch, pei m e ly. ad pt d ca n h. c rren .9 a n lwhfitr in. tr. d c de W i g e lo n rad i i is: quen'cies in a'ran'ge from 400 kilocycles to 1000 c y sl... c

b e t Of h s inv i nisl o was ani lm o dy e fii ntl 1 i' nd' n in. wh hi he e eeii e cul t n blins fl id-1 W nether pbject of this invention is theuse' of ai rolled c n'dens having af cobling reservoii lo f catedat" each oithe' ends; of-tnee demr rolls; with fluid cooling? tubes within and out side the condenser un it's. 1 V

A feature o f this invention is the novel arrange ment ofth capacitive units within a metallic casing; the units being interposed between two fluid reservoirs through which poolin fluid passes from one end of the condenser to another.

Althoughelectriccondensershaving fluid cooling means are old in the art, they areunable to, stand the excessive heating which encountered in high frequency electric welding. By the improved cooling method of this invention and by the use oi: an. improved dielectric material for. the condenser units, a device has beenldevised which..will overcome the .objections of th': prior art? The.condenser of thisinventlonis' capable of operating. continuously in radio frequen y electric welding "circuits having 11000 volts and carrying. 1,000. amperes.

. This invention. will best, be understood by referring' .to the" accompanying drawing in which: Fig.1 is a plan view of the condenser of this invention;

Fig. 211s a;longitudinal sectiohsofFig.

Fig.3 is a cross. section of Fig.1v shown partly in elevation, and

Fig. 4 is a radio'frequency' circuit showing a use of the condenser of this invention.

Rferring now in detail t6 the drawing, a metallie casing I- having a cover arranged to enclose" a plurality of condenser units. The" side walls of casing I support two high current welding terminals 3 and 4 which are located in the central portion and extend outward from the ends of the casing. A cooling fluid of oil 50 is placed within casing l. The terminal 3 is composed of a metallic tube which is provided with insulating bushings 5A and 53, each one of the insulating bushings 5A and 5B being arranged concentric with the metallic terminal tube 3 which is insulatingly secured to casing I by passing over the insulating bushing 5 and 'ements are cooled a1 iii then through bushing 5A, th latter bushing 12f, s i r d" t he ce ra ort fifl il el y; passin u h a ap e 6- fh bu' h 51?; then camps bushing 5A to the side of the cas n'g I The terminal 4 includes a metal. bushing I rounding an inlet conduit B WhiCh conduitpas A through an aperture, 1 in casing Anou' tletfi f'id i d f Pas Q n h h h ni a iri rtie 9i. insulating bushing 5. The portionoi co'ridu e; within casing l is provide thizwo threaded: i-ilbb'ws l 0 and H which support one end of a m e}. tallic reservoir l2 for example, made of copp; a The'porti'on of conduit 9 which is inside th" ca ing is also provided with two elbows ld an which terminate in a second or lowerreseivon; f5. Inlet conduit 8 and outlet 9 are'both thr'ea ded at 5'] to permit assembly within casing" I A; radiating and terminal conductor plate [6 is;

. spaced directly ben'eath the upper reservoir [2" and is insulated therefrom. A second radiiatif and terminal plate IT is placed inthrmalarid" elctricalQcontact with the lower reservoir l5 which p1ate also serves asa support; Intel: 7 posed between conducting plate I6 and the lower,

reservoir l5 there are arranged a plurality or rolled condenser units I8. The condenser units f8 are especially constructed as shown in detail by Fig". 3. A'm'etallic tube I 9 formsboth a cooling tube and a Winding mandrel for the condenser unit. In order to prevent short circuiting" of: the condenser layers, the upper end of tube [9" is partly covered with an insulatingtube 20'. Where cooling conditions will permit, tube 19 may be er glass with a: silver plated band at each'end. The platedband'o'f' tube I9 is then soldered directlylto each one of the reservoirs and the insulating: tube 20 canthen be omitted- Upon the tube l9 are wound two layers of a dielectric material 22,. which are preferably of polystyrene ribbonfa'rid then, two layers of metallic foil such...as,. for exampldlead foil Z]. The dielectric material. 22v insulates each metallic foil by being interposed. therehetxveen. One end of eachstrip. ofthe ream foilsll is arranged to extend alternately beyond th dielectric ribbons 22, and for making electrical connection thereto, metallic cup-shaped discs 23 and 24 are located at the condenser rolled ends. The rim of discs 23 are soldered to the projecting metallic foils of th condenser. The foils and polystyrene ribbons are wound with a plurality of turns, sufiicient to give a desired capacity. As will be seen in Fig. 1, there are four rows of condenser units placed along one direction of the casing and five rows in the other direction, thus making the total of twenty condenser 3 units connected in parallel. The capacity of each unit is .02 microfarad and when twenty units are used, the capacity will be .4 microfarad total. A larger or smaller amount may be employed to give a different value of capacity. The top end caps 23 are all soldered to plate l6, which has a corresponding number of holes to receive the insulating tubes 20 which project sufficiently beyond the surface of plate IE to provide the proper insulation for 1000 volts. The metallic tube I9 continues beyond the disc 23' and is placed in fluid communication with the upper reservoir I2, the tube I9 being soldered to the bottom of reservoir I2 to prevent leakage of the fluid. The end discs 24 are spaced slightly above reservoir I5 and at this end, only the metal tube I9 of each unit projects therethrough, the tubes being soldered to the upper portion of the reservoir I5 in a manner similar to that mentioned above, in order to prevent leakage of the fluid. Q

A plurality of glass cooling tubes 30 with silver plated end bands are arranged to extend from one reservoir to another. The tubes 30 are spaced between the condenser units to aid in cooling the outside of the rolls. A band of silver plating 3| at each end of the tube 30 is provided to solder the tubes to the reservoirs.

In assembling the device of this invention, the two reservoirs I2 and I5 are first connected to conduits B and 9 by means of elbows I and II, I3 and I4. The plate I6 is then assembled with the insulating bushing 5, A, 5B and metallic bushing 3, this arrangement being such as to insulate one portion of the condenser from that of the casing and upper reservoir I2. The plate I! is then placed in position by being bent up and placed along side of bushing 4 and electrically connected thereto. The entire unit is thenassembled with the condenser units and glass tubes 30 in their proper positions, as shown by the drawings. The entire unit is then placed within a metal casing I and the casing is filled with a high grade of insulating oil which provides suitable electric insulation and also assists in the cooling of the condenser unit. The terminal bushings 3 and 4 of suflicient size to carry a thousand amperes or more, and arranged to connect with the electrodes of the welding machine by having the terminals clamped between clamp nuts 25 and lock nuts 26.

Fig. 4 shows the circuit arrangement wherein a work coil 40 is connected to the condenser 4| of this invention. An oscillator inductance coil 42 connects to condenser 4| of a tank circuit. Coil 40 is cooled by the same fluid source as condenser 4|.

This invention should not be limited to the precise arrangement shown.

What is claimed is:

1. A fluid cooling system for electrical apparatus comprising a casing for enclosing said electrical apparatus, a first fluid reservoir, a second fluid reservoir, an electrical terminal plate interposed between said reservoirs, a plurality of electrical devices each one of which is interposed between said terminal plate and said second reservoir, and fluid cooling means passing through a hollow core in said electrical devices and in fluid communication between said first and second reservoirs for cooling said devices, a metallic bushing located in said casing for supporting said terminal plate from said casing, and an inlet and an outlet tube insulatingly passing through the walls of said casing, said outlet tube passing through said metallic bushing, said inlet and outlet tubes connecting said first and second fluid reservoirs with an outside fluid supply source to form a circulating fluid path from one reservoir through the hollow core to the other reservoir to cool said electrical devices.

2. A fluid cooling system for electrical apparatus comprising a metallic casing containing an insulating oil, a pair of parallelly arranged reservoirs within said casing, an electrical terminal plate interposed between said reservoirs, a plurality of electrical devices interposed between said terminal plate and one of said reservoirs, fluid cooling means in fluid communication between said parallelly arranged reservoirs including a plurality of tubes some of which pass through each one of said electrical devices, others of said tubes being arranged outside of said electrical devices, a fluid inlet connected to one of said reservoirs and passing through the wall of said casing to permit cooling fluid to flow from one reservoir to the other reservoir through all of said tubes, and a fluid outlet tube insulatingly passing through the wall of said casing and in fluid communication with the other of said reservoirs.

RUSSELL E. HERR.

LANNES E. ANDERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Re. 15,642 Smith July 3, 1923 1,536,948 Thomson May 5, 1925 1,580,873 Weldon Apr. 13, 1926 1,942,153 Seeley Jan. 2, 1934 1,991,707 Silbermann Feb. 19, 1935 2,050,587 Ruben Aug. 11, 1936 2,098,746 Hansson Nov. 9, 1937 2,177,266 Schupp Oct. 24, 1939 2,256,757 Durand Sept. 23, 1941 2,306,527 Daniels Dec. 29, 1942 2,326,151 Marbury Aug. 10, 1943 2,359,174 Vogel Sept. 26, 1944 2,403,969 Fledel-Beck July 16, 1946 FOREIGN PATENTS Number Country Date 218,588 Switzerland Apr. 1, 1942 335,829 Great Britain Oct. 2, 1930 378,656 Great Britain Aug. 18, 1932 

